Perfluorinated ion-exchange microcomposite catalysts modified with Lewis acid

ABSTRACT

This invention concerns a modified porous microcomposite comprising a perfluorinated ion-exchange polymer entrapped within and highly dispersed throughout a network of inorganic oxide wherein the network and optionally the pendant groups of the polymer have been modified with a Lewis acid. These modified microcomposites can be used in catalyst compositions for various chemical processes, such as in the alkylation or acylation of aromatics.

This is a division of application Ser. No. 09/070,041 filed Apr. 30,1998 now U.S. Pat. No. 5,932,511 which claims priority benefit ofProvisional Application No. 60/047,969, filed May 28, 1997.

FIELD OF THE INVENTION

This invention concerns catalysts comprising chemically modifiedperfluorinated ion-exchange microcomposites, processes for theirpreparation and their use as catalysts in chemical processes.

TECHNICAL BACKGROUND

K. A. Mauritz et al., Polym. Mater. Sci. Eng. 58, 1079-1082 (1988), inan article titled "Nafion-based Microcomposites: Silicon Oxide-filledMembranes", discuss the formation of micro composite membranes by thegrowth of silicon oxide microclusters or continuous silicon oxideinterpenetrating networks in pre-swollen "NAFION®" sulfonic acid films.NAFION® is a registered trademark of E. I. du Pont de Nemours andCompany.

U.S. Pat. No. 4,038,213 discloses the preparation of catalystscomprising perfluorinated ion-exchange polymers containing pendantsulfonic acid groups on a variety of supports.

The catalyst utility of perfluorinated ion-exchange polymers containingpendant sulfonic acid groups, supported and unsupported has been broadlyreviewed: G. A. Olah et al., Synthesis, 513-531 (1986) and F. J. Waller,Catal. Rev.-Sci. Eng., 1-12 (1986).

WO 95/19222 describes a porous microcomposite comprising aperfluorinated ion-exchange microcomposite containing pendant sulfonicacid and/or carboxylic acid groups entrapped within and highly dispersedthroughout a network of metal oxide. These catalysts are differentiatedfrom NAFION® supported catalysts in that by virtue of the preparation ofthe microcomposite catalyst, the polymer becomes intimately mixed with ametal oxide precursor in solution, and thus becomes thoroughly entrappedand highly dispersed throughout a resulting network of metal oxide. Withthe polymer being mechanically entrapped within the metal oxide networkand not merely on the surface of a support, as is the case in supportedcatalysts, the catalytic activity of these microcomposite catalysts issignificantly increased.

R. S. Drago et al., in "Preparation and Catalytic Activity of a NewSolid Acid Catalyst", J. Am. Chem. Soc. 110, 3311-3312, 1988 describethe preparation of a catalyst prepared by reacting an inorganic oxidewith aluminum chloride in refluxing carbon tetrachloride. Resultssuggested that over 90% of the chloroaluminum species on the support hadthe composition (--O--)AlCl₂.

Although a variety of reactions can be beneficially catalyzed by thecompounds and the composites cited above, there is still a need forcatalysts of increased activity and selectivity and useful in a broadrange of applications.

SUMMARY OF THE INVENTION

The present invention provides a modified porous microcomposite,comprising: a perfluorinated ion-exchange polymer containing pendantgroups selected from the group consisting of: sulfonic acid groups,metal sulfonate groups, alkyl metal sulfonate groups, metal halidesulfonate groups, alkyl metal halide sulfonate groups, sulfonicacid/Lewis acid complex groups, and any combination of said groups,wherein the polymer is entrapped within and highly dispersed throughouta network of inorganic oxide, said network having a plurality of metaloxy species bonded thereto, said metal oxy species being selected fromthe group consisting of: a metal oxy halide, an alkyl metal oxy halide,and an alkyl metal oxy.

The present invention also provides a process for the preparation of amodified porous microcomposite, comprising the steps of: contacting aporous microcomposite comprising a perfluorinated ion-exchange polymercontaining pendant sulfonic acid groups, wherein said polymer isentrapped within and highly dispersed throughout a network of inorganicoxide, with a Lewis acid for a time sufficient to convert a plurality ofhydroxyl groups of the inorganic oxide network to a metal oxy speciesselected from the group consisting of: a metal oxy halide, an alkylmetal oxy halide, and an alkyl metal oxy.

The present invention also provides a process for the preparation of amodified porous microcomposite, comprising the steps of: contacting ametal oxide with an aqueous solution comprising a perfluorinatedion-exchange polymer containing pendant sulfonic acid groups to form apolymer/metal ion solution; adding to the polymer/metal ion solution ahydrolyzed inorganic oxide; allowing network formation of the inorganicoxide to occur; and recovering a modified porous microcompositecomprising a perfluorinated ion-exchange polymer containing pendantgroups selected form the group consisting of: sulfonic acid groups,metal sulfonate groups, alkyl metal sulfonate groups, metal halidesulfonate groups, alkyl metal halide sulfonate groups, sulfonicacid/Lewis acid complex groups, and any combination of said groups,wherein the polymer is entrapped within and highly dispersed throughoutthe network of inorganic oxide, said network having a plurality of metaloxy species bonded thereto.

The present invention further provides an improved method for alkylatingan aromatic compound, the improvement comprising using an effectiveamount of a catalyst composition comprising a modified porousmicrocomposite comprising a perfluorinated ion-exchange polymercontaining pendant groups selected from the group consisting of:Sulfonic acid groups, metal sulfonate groups, alkyl metal sullonategroups, metal halide sulfonate groups, alkyl metal halide sulfonategroups, sulfonic acid/Lewis acid complex groups, and any combination ofsaid groups, wherein the polymer is entrapped within and highlydispersed throughout a network of inorganic oxide, said network having aplurality of metal oxy species bonded thereto, said metal oxy speciesbeing selected from the group consisting of: a metal oxy halide, analkyl metal oxy halide, and an alkyl metal oxy.

DETAILED DESCRIPTION OF THE INVENTION

It is well known in the literature that Lewis acids catalyze a range ofreactions, for example alkylations, acylations, esterifications, andisomerizations. Imparting Lewis acid character to a known porousmicrocomposite yields herein novel catalysts which can possess improvedactivity in these types of reactions. While not intending to be bound byany mechanism, it is believed that key features of the present inventioninclude the modification of a plurality of the residual hydroxyl groupsof the inorganic oxide network to metal oxy species, and optionalmodification of all or a portion of the pendant sulfonic acid groups ofa perfluorinated ion-exchange polymer of a porous microcomposite tometal sulfonate groups, alkyl metal sulfonate groups, metal halidesulfonate groups, alkyl metal halide sulfonate groups, sulfonicacid/Lewis acid complex groups, or any combination of said groups.

The present invention concerns the modification of a porousmicrocomposite. By "porous microcomposite" is meant a compositioncomprising a perfluorinated ion-exchange polymer (PFIEP) containingpendant sulfonic acid groups, wherein said polymer is entrapped withinand highly dispersed throughout a network of inorganic oxide. The PFIEPmay optionally further comprise pendant carboxylic acid groups. Thepercentage of the perfluorinated ion-exchange polymer in themicrocomposite is from 0.1 to about 90% by weight and the size of thepores in the microcomposite is about 1 nm to about 75 nm, and themicrocomposite optionally further comprises pores having a size in therange of about 75 nm to about 1000 nm. Such microcomposites aredescribed in U.S. application Ser. No. 08/574,751, filed Dec. 19, 1995incorporated by reference herein and in the corresponding PCTpublication WO 95/19222. The microcomposite can be in any size or shapeto be utilized in the present invention, such as ground into particlesor shaped into spheres. The PFIEP is, preferably, a sulfonated NAFION®PFIEP. The weight percentage of PFIEP preferably ranges from about 5% toabout 80%, most preferably from about 10% to about 15%. The inorganicoxide of the network is preferably silica, alumina, titania, germania,zirconia, alumino-silicate, zirconyl-silicate, chromic oxide, ironoxide, or mixture thereof; most preferably silica.

The inorganic oxide network of the present modified porousmicrocomposite has a plurality of metal oxy species bonded thereto. By"having a plurality of metal oxy species bonded thereto" is meant that aportion of the hydroxyl groups of the inorganic oxide network of theporous microcomposite, preferably at least 50% of the hydroxyl groups,most preferably at least 80% of the hydroxyl groups, are converted to ametal oxy species via reaction with a Lewis acid, and this metal oxyspecies remains bonded to the inorganic oxide network of the modifiedporous microcomposite.

As is known after formation of an inorganic oxide network, there arenumerous residual hydroxyl groups. This is because during networkformation each of the inorganic atoms become constituents of a networkstructure via bonds to other inorganic atoms through oxygen butcondensation to form these crosslinks does not go to 100% completion;there are residual, uncrosslinked hydroxyl groups. For example, in thepresent case where the inorganic oxide of the network is silica, silanol(Si--OH) groups can be found as part of the network, and it is aplurality of the hydroxyl (--OH) groups of these silanols that areconverted to metal oxy species which remain bonded to the network.

By "metal oxy species" is meant a group selected from the groupconsisting of: a metal oxy halide group, an alkyl metal oxy halidegroup, and an alkyl metal oxy group. A metal oxy species can berepresented by the formula - MR_(q) X_(n-1), wherein, M is a metal froma Lewis acid, R is a monovalent hydrocarbon radical, X is a halideselected from the group consisting of: Cl, Br and F; q is an integerranging from 0 up to an integral value such at q+n is equal to theoxidation state of M; and n is an integer ranging from 1 up to anintegral value such that q+n is equal to the oxidation state of M. Thus,the particular kind of metal oxy species that is bonded to the inorganicoxide network depends on the values of q and n-1. For example, when q=0,a metal oxy halide species results; when n-1=0, an alkyl metal oxyspecies results, and when both q and n-1 are greater than 0, an alkylmetal oxy halide results. Representative examples of metal oxy speciesare --OAlCl₂, --OBCl₂, --OAl(CH₃)Cl, --OAl(CH₂ CH₃)Cl, --OAl(CH₂ CH₃)₂,--OZnCl, --OTiCl₃, and --OSnCl₃.

As is shown below, when a Lewis acid, which can be of the formula MR_(q)X.sub., wherein M, R and X are as defined above, reacts with thehydroxyl group of the inorganic oxide network of the porousmicrocomposite, the metal oxy species is formed and is bonded to thenetwork. This process is described in more detail below. ##STR1## HX orHR is a byproduct of the reaction. For example, the Lewis acid, CH₃ CH₂AlCl₂, will give the metal oxy species --OAlCl₂ and the byproduct CH₂CH₂ --H.

The pendant groups of the PFIEP of the modified porous microcompositecan be sulfonic acid groups, metal sulfonate groups, alkyl metalsulfonate groups, metal halide sulfonate groups, alkyl metal halidesulfonate groups, sulfonic acid/Lewis acid complex groups, or anycombination of said groups. Optionally, the PFIEP of the modified porousmicrocomposite may further comprise carboxylic acid groups, metalcarboxylate groups, alkyl metal carboxylate groups, metal halidecarboxylate groups, alkyl metal halide carboxylate groups, carboxylicacid/Lewis acid complex groups, or any combination of said groups.Depending on the nature of the pendant groups of the PFIEP, the modifiedporous microcomposite can be Lewis acid and/or Bronsted acid incharacter. Included within the definition of "pendant" are thoseembodiments wherein two or more pendant groups are bridged to each otherthrough a metal halide group, an alkyl metal halide group or a metalalkyl group. For example, PFIEP within a modified porous microcompositecould have the following structure: R_(f) --SO₃ --TiCl₂ --SO₃ --R_(f).Other representative bridging configurations are: R_(f) --SO₃--Al(Cl)--SO₃ --R_(f), R_(f) --SO₃ --Al(CH₂ CH₃)--SO₃ --R_(f) ; R_(f)--SO₃ --Ti(Cl)(CH₂ CH₃)--SO₃ --R_(f), and R_(f) --SO₃ --Zr(Cl)₂ --SO₃--R_(f).

The sulfonic acid groups are of the formula --SO₃ H. The metal sulfonategroups, alkyl metal sulfonate groups, metal halide sulfonate groups andalkyl metal halide sulfonate groups can be of the formula

    --(SO.sub.3).sub.m MR.sub.q X.sub.n-1

wherein:

M is a metal selected from the group consisting of: Al, B, Ti, Fe, Zn,Ga, Sn, Sb,

Zr, Ta, Sc, Yb, Rh, Pd and La, preferably Al, B, Ti, and Sn;

R is a monovalent hydrocarbon radical, preferably C₁ to C₁₂ alkyl oraryl;

X is a halide selected from the group consisting of: Cl, Br and F;

q is an integer ranging from 0 up to an integral value such that q+m+n-1is equal to the oxidation state of M;

m is an integer ranging from 1 up to the oxidation state of M; and

n-1 is an integer ranging from 0 up to an integral value such thatq+m+n-1 is equal to the oxidation state of M.

Thus, the particular kind of pendant metal sulfonate group of the PFIEPof the modified porous microcomposite represented by the formula abovedepends on the values of q and n-1. For example, when q=0 and n-1=0, thependant group is a metal sulfonate group; when n-1=0, the pendant groupis an alkyl metal sultonate group; when q=0 and n-1 is greater than 0,the pendant group is a metal halide sulfonate group; and when both q andn-1 are greater than 0, the pendant group is an alkyl metal halidesulfonate group. Representative examples of metal sulfonate groups are--SO₃ AlCl₂, --(SO₃)₂ AlCl, --(SO₃)₃ Al, --SO₃ TiCl₃, --(SO₃)₂ TiCl₂,--(SO₃)₃ TiCl, --(SO₃)₄ Ti, --SO₃ BCl₂, --(SO₃)₂ BCl, --(SO₃)₃ B,--(SO₃)₃ Sc, and --(SO₃)₃ Yb, --(SO₃)₂ Al(CH₂ CH₃), and --(SO₃)₂Ti(Cl)(CH₂ CH₃).

The sulfonic acid/Lewis acid complex groups are "superacid" groups whichcan be of the formula --(SO₃)_(m) H•MR_(q) X_(n) Representative examplesof sulfonic acid/Lewis acid complex groups are --(SO₃)HF•BF₃ and--(SO₃)H•SbF₅.

Preferably, the PFIEP of the modified porous microcomposite containssulfonic acid groups and metal halide sulfonate groups. Most preferablyPFIEP with these groups are about 10 to about 25% by weight of themodified microcomposite.

This invention further provides a process for the preparation of saidmodified porous microcomposite comprising contacting a porousmicrocomposite, as defined above, with an effective amount of a Lewisacid for a time sufficient to convert a plurality of hydroxyl groups ofthe inorganic oxide network to metal oxy species. Preferably, the Lewisacid is a compound of the formula MR_(q) X_(n) wherein:

M is a metal selected from the group consisting of: Al, B, Ti, Fe, Zn,Ga, Sn, Sb,

Zr, Ta, Sc, Yb, Rh, Pd and La, preferably Al, B, Ti or Sn.

R is a monovalent hydrocarbon radical, preferably a C₁ to C ₁₂ alkyl oraryl;

X is a halide selected from the group consisting of: Cl, Br and F;

q is an integer ranging from 0 up to an integral value such that q+n isequal to the oxidation state of M;

n is an integer ranging from 0 up to an integral value such that q+n isequal to the oxidation state of M.

Representative examples of Lewis acids are AlCl₃, TiCl₄, BCl₃, ZrCl₄,ZnCl₂, Zn(C₂ H₅)₂, and Al(CH₂ CH₃)Cl₂. A preferred Lewis acid is AlCl₃.

Contact of the porous microcomposite with the Lewis acid can beaccomplished in a number of ways, for example, in a gas phase, in aliquid phase or via sublimation, depending on the Lewis acid selected.

In the gas phase, the porous microcomposite can be placed in a glasstube in flowing dry nitrogen, with optional heat (just above roomtemperature to about 200° C.). and allowed to react in this gas phasewith a Lewis acid, for example aluminum chloride, ethylaluminumchloride,or TiCl₄. The resulting vapors pass over the microcomposite at atemperature ranging from about room temperature to about 280° C. for atime sufficient to convert a plurality of the hydroxyl groups of theinorganic oxide network to metal oxy species. During the presentprocess, the pendant sulfonic acid groups of the PFIEP can remainunchanged or all or a portion of said pendant sulfonic acid groups canbe converted to metal sulfonate groups, alkyl metal sulfonate groups,metal halide sulfonate groups, alkyl metal halide sulfonate groups,sulfonic acid/Lewis acid complex groups, or any combination of saidgroups. After completion of the reaction, Lewis acid and any byproductsof the reaction can be removed by heating the product in vacuum.

In a liquid phase embodiment, a porous microcomposite which has beendried can be reacted with a Lewis acid dissolved in a solvent.Representative examples of dissolved Lewis acids are AlCl₃ dissolved innitromethane, EtAlCl₂ dissolved in hexane, BCl₃ dissolved in heptane,and the like. Mixtures of alkylchlorotitanium compounds or mixtures ofalkylchloroboron compounds are also suitable Lewis acids. The processcan be conducted at reflux temperature, the product filtered and washedwith a solvent. Suitable solvents include, but are not limited to,alkanes, nitromethane or ether.

The modified porous microcomposite of the present invention can also beprepared using sublimation. For example, sublimation of AlCl₃ at atemperature ranging from about room temperature to about 200° C. invacuum in the presence of the porous microcomposite will yield amodified porous microcomposite having a metal oxy species bonded to theinorganic oxide network. Depending on process conditions, the pendantgroups of the PFIEP of the resulting modified porous microcompositecould be selected from: sulfonic acid groups, aluminum sulfonate groups,aluminum chloride sulfonate groups, or any combination of said groups.Any excess AlCl₃ can be removed by applying vacuum to the modifiedmicrocomposite, optionally with heat.

In cases where the microcomposite is contacted with a Lewis acid whichis an alkyl metal compound, such as triethylaluminum (Et₃ Al) ortrimethylboron (Me₃ B), to form a modified microcomposite having pendantalkyl metal sulfonate groups, the process may further comprisecontacting the modified microcomposite with a source of halogen.Preferably the halogen source comprises chloride or alkyl chloride, suchas tert butyl chloride. By contacting the modified microcomposite with asource of halogen, a new modified porous microcomposite is generatedwhich can have pendant metal halide sulfonate groups (and pendant alkylmetal halide sulfonate groups), such as aluminum chloride, in additionto, or in lieu of the pendant alkyl metal sulfonate groups. In thisembodiment, the microcomposite can be reacted either in the gas phase,as described above, or in a liquid phase using the alkyl metal compoundin a suitable solvent, such as hexane. The modified microcomposite canbe dried in vacuum and is preferably kept free from moisture by storingit in an inert atmosphere.

It is preferred that the porous microcomposite, as defined above, be dryprior to contact with the Lewis acid and that the present process becarried out under essentially anhydrous conditions.

In the process of the present invention, the conditions can be varied toalter the extent of halide or hydrocarbon radical, R, loss. For example,with a large excess of Lewis acid, such as ZrCl₄, zinc chloro sulfonategroups can be obtained as pendant groups of the PFIEP. However, with anexcess of the sulfonate within the microcomposite, all of the halidegroups of the Lewis acid may combine with the hydrogen from the pendantsulfonic acid groups of the PFIEP of the porous microcomposite whereinthe pendant groups of the PFIEP of the resulting modified porousmicrocomposite can be of the metal sulfonate type, --(SO₃)₄ Zr.

In an embodiment of this invention, the porous microcomposites can bemodified with certain Lewis acids to give solid acids with greatlyincreased acid strength, i.e. superacids. Boron trifluoride is anexample of such a Lewis acid. The porous microcomposite can be reactedwith BF₃ in the gas phase to functionalize the sulfonic acid resultingin a pendant sulfonic acid/Lewis acid complex group, --SO₃ H⁺ •BF₃. Theporous microcomposite can be treated either in the gas phase or in theliquid phase, optionally with a solvent present, to yield a series ofadducts which have high acid strength. Other Lewis acids usable in thisembodiment of the invention include, but are not limited to, SbF₅ andTaF₅. When SbF₅ is employed, functional groups of the kind --SO₃ •SbF₅are the result.

The present invention also provides a process for the preparation of themodified porous microcomposite described above, comprising the steps of:contacting a metal oxide with an aqueous solution comprising aperfluorinated ion-exchange polymer containing pendant sulfonic acidgroups to form a polymer/metal ion solution; adding to the polymer/metalion solution a hydrolyzed inorganic oxide; allowing network formation ofthe inorganic oxide to occur; and recovering the modified porousmicrocomposite. It is believed this process of preparing the modifiedporous microcomposite can promote crosslinking resulting in bridgedpendant groups. In this process a metal oxide, preferably anacid-soluble metal oxide, such as certain transition metals orlanthandies, for example, scandium oxide or ytterbium oxide, iscontacted with an aqueous solution comprising a perfluorinatedion-exchange polymer containing pendant sulfonic acid groups. Suchaqueous solutions of PFIEP are available from Aldrich Chemical Co.,Milwaukee, Wis., or PFIEP solutions generally can be prepared using theprocedure of U.S. Pat. No. 5,094,995 and U.S. Pat. No. 4,433,082,incorporated by reference herein. The process may further comprise thestep of heating the aqueous polymer solution and the metal oxide toenable the metal oxide to dissolve. To the resulting polymer/metal ionsolution is added a hydrolyzed inorganic oxide. Such inorganic oxidecompounds can be the same as those described above and can be hydrolyzedby conventional methods. Network formation of the inorganic oxide isallowed to occur. Gelation may in some instances self-initiate or inothers can be facilitated by adjusting the pH with acid or base, such asNaOH. The modified microcomposilte can be dried and subsequently washedwith deionized water. The dried microcomposite can be optionally washedwith various degrees of an acid, such as nitric acid.

The utility of the modified porous microcomposites of the presentinvention is in catalyst compositions including use, for example, inalkane isomerization or petroleum cracking processes. The modifiedporous microcomposite of the present invention can also be used incatalyst compositions for alkylations, acylations, esterifications, orisomerizations.

Thus, the present invention provides an improved method for alkylatingan aromatic compound, the improvement comprising using an effectiveamount of a catalyst composition comprising the modified porousmicrocomposite described above.

EXAMPLES

A 13 wt % NAFION® resin in silica microcomposite catalyst, referred toin the examples below as the unmodified microcomposite, was prepared asdescribed in the next paragraph using a NAFION® PFIEP NR 005 solution.NAFION® PFIEP NR 005 solution is available from DuPont NAFION® Products,Fayetteville, N.C., is also known as NAFION® SE-5110, and is preparedfrom resin which is approximately 6.3 tetrafluoroethylene molecules forevery perfluoro(3,6-dioxa-4-methyl-7-octenesulfonyl fluoride) molecule(CF₂ ═CF--O--(CF₂ CF(CF₃)--O--CF₂ CF₂ --SO₂ F). After hydrolysis of theresin, the PFIEP has an equivalent weight of approximately 1070.,NAFION® PFIEP solutions can be purchased from Aldrich Chemical Co.,Milwaukee, Wis., or PFIEP solutions generally can be prepared using theprocedure of U.S. Pat. No. 5,094,995 and U.S. Pat. No. 4,433,082.

204 g of tetramethoxysilane (TMOS), 33 g of distilled water and 3 g of0.04 M HCl was stirred for 45 min to give a clear solution. To 300 mL ofa NAFION® PFIEP solution was added 150 mL of a 0.4 M NaOH solution,while the PFIEP solution was being stirred. After addition of the NaOHsolution, the resulting solution was stirred for a further 15 min. TheTMOS solution was added rapidly to the stirred PFIEP solution. Afterabout 10-15 sec, the solution gelled to a solid mass. The gel was placedin an oven and dried at a temperature of about 95° C. over a period ofabout 2 days followed by drying under vacuum overnight. The hard,glass-like product was ground and passed through a 10-mesh screen. Thematerial was then stirred with 3.5M HCl for 1 hour (with 500 mL ofacid), followed by washing with 500 mL deionized water. The solid wascollected by filtration. Acidification, washing and filtration wererepeated a total of 5 times and after the final wash the solid was driedunder vacuum at 100° C. for 24 hours.

EXAMPLE 1 Treatment of a Porous Microcomposite with Aluminum Chloride inthe Gas Phase

5 g of an unmodified microcomposite (as prepared above) was placed in avertical tube (held in place by glass wool), and 5 g of AlCl₃ was placedabout 4-6 cm beneath the AlCl₃. The tube and contents were heated to175° C. with a slow stream of nitrogen passing through the tube for 4hours. The product (5.3 g) was removed following reaction, and Al and Clwere shown to be present using chemical analysis.

Example 2 Treatment of a Porous Microcomposite with Aluminum Chloridevia Sublimation

5g of an unmodified microcomposite (as prepared above) was reacted viasublimation of the AlCl₃ at 125° C. in vacuum by placing the AlCl₃ (5g)in the bottom of a glass tube over which a layer of glass wool wasplaced and on top of that the microcomposite was placed. The tube andcontents were heated under vacuum at 125° C. for 8 hrs and the aluminummodified microcomposite was removed from the tube under a nitrogenatmosphere. The Al content was 1.7 wt %.

Example 3 Treatment of a Porous Microcomposite with Aluminum Chloride inthe Gas Phase

5 g of an unmodified microcomposite (as prepared above) was placed in avertical tube (held in place by glass wool), and 10 g of AlCl₃ wasplaced about 4-6 cm beneath the AlCl₃. The tube and contents were heatedto 200° C. with a slow stream of nitrogen passing through the tube for 9hours. The product (5.15 g) was removed following reaction, and Al andCl were shown to be present using chemical analysis.

Example 4 Treatment of a Porous Microcomposite with Aluminum Chloride inthe Gas Phase

5 g of an unmodified microcomposite (as prepared above) was placed in avertical tube (held in place by glass wool), and 10 g of AlCl₃ wasplaced about 4-6 cm beneath the AlCl₃. The tube and contents were heatedto 170° C. with a slow stream of nitrogen passing through the tube for 4hours. The product (5.3 g) was removed following reaction, and Al and Clwere shown to be present using chemical analysis.

Example 5 Treatment of a Porous Microcomposite with Aluminum Chloride inthe Liquid Phase

5 g of AlCl₃ was added to 100 ml of freshly distilled CCl₄ and to thiswas added 5 g of an unmodified dried microcomposite (as prepared above).The mixture was stirred for 6 hours under reflux under a stream of drynitrogen. The solid product was filtered, washed with excess CCl₄ anddried in vacuum. Moisture was excluded by working under an inertatmosphere.

Example 6 Treatment of a Porous Microcomposite with Triethylaluminum

5 g of an unmodified microcomposite (as prepared above) was reacted with20g of triethylaluminum (1M in hexane) and left to react for 24 hr atroom temperature. Upon contact of the microcomposite with thetriethylaluminum, the flask and contents got warm with the temperaturerising to 40° C. The solid product was filtered in dry nitrogen, washedwith dry hexane and then dried in vacuum.

Example 7 Treatment of a Porous Microcomposite with TiCl₄

30 g of TiCl₄ was cooled using a carbon dioxide/acetone bath (-78° C.)and then was added to 5 g of dried microcomposite. This was left to warmovernight to room temperature and the excess TiCl₄ was removed undervacuum to yield the titanium chloride modified material. The percent ofTi found in the modified microcomposite was 1.77.

Example 8 Treatment of a Porous Microcomposite with BCl₃

20 g of BCl₃ in hexane (Aldrich) was cooled using a carbondioxide/acetone bath (-78° C.) and then was added to 5 g of driedmicrocomposite. This was left to warm overnight to room temperature, andthe excess BCl₃ was removed under vacuum to yield the titanium chloridemodified material. The percent of B found in the modified microcompositewas 0.4.

Example 9 Treatment of a Porous Microcomposite with Al(C₂ H₅)Cl₂

20 g of Al(C₂ H₅)Cl₂ in hexane (Aldrich ) was cooled using a carbondioxide/acetone bath (-78C) and then was added to 10 g of driedcomposite. This was left to warm overnight to room temperature and theexcess Al(C₂ H₅)Cl₂ was removed under vacuum to yield the titaniumchloride modified material. The percent of Al found in the modifiedmicrocomposite was 1.78.

Example 10 Benzene Pronylation Catalyzed by Solid Acid Catalysts

Four samples of an Al₂ O₃ modified microcomposite and one sample of anunmodified microcomposite (as prepared above) were tested as solid acidcatalysts in a benzene propylation to cumene. The alkylation reactionwas carried out in the liquid phase under ambient pressure at 70° C. bybubbling propylene through the neat benzene solution containing thesolid acid catalyst. The benzene solution was presaturated withpropylene at the reaction temperature and then the catalyst was added.For each run 1 g of the solid acid catalyst was added to a flaskcontaining 50 g of benzene. Liquid samples were taken at certain timeintervals and analyzed by gas chromatography. Table 1 lists the reactionrate and benzene conversion to cumene after 1 hr at 70° C. over the fivecatalysts.

                  TABLE 1                                                         ______________________________________                                                       Reaction                                                         Catalyst Rate (mM/gcat.gr) Cumene Yield (%)                                 ______________________________________                                        Unmodified Microcomposite                                                                    30.0         3.8                                                 Modified Microcomposite of 148.0 8.5                                          Example 1                                                                     Modified Microcomposite of 548.0 34.8                                         Example 2                                                                     Modified Microcomposite of 99.2 5.0                                           Example 3                                                                     Modified Microcomposite of 94.3 6.4                                           Example 4                                                                   ______________________________________                                    

Example 11 Synthesis of Scandium Modified Microcomposites

0.1 g of scandium oxide was added to a NAFION® solution (10 wt %) inwater. The solution and oxide was heated to 100° C. for 1 hour at whichpoint the oxide dissolved. To this solution was added a solution oftetramethoxysilane which had been hydrolyzed by mixing 40 g oftetramethoxysilane, 6 g of water and 0.6 g of 0.04M HCl and stirringstirred for one hour. To this was added 12 mls of 0.4M NaOH and thesystem gelled. The gel was dried in a steam of nitrogen at 90° C., andthe dried gel was washed with 5 liters of deionized water.

What is claimed is:
 1. In a method of alkylating an aromatic compound,the improvement comprising using an effective amount of a catalystcomposition comprising a modified porous microcomposite catalystcomprising a perfluorinated ion-exchange polymer containing pendantgroups selected from the group consisting of: sulfonic acid groups,metal sulfonate groups, alkyl metal sulfonate groups, metal halidesulfonate groups, alkyl metal halide sulfonate groups, sulfonicacid/Lewis acid complex groups, and any combination of said groups,wherein the polymer is entrapped within and highly dispersed throughouta network of inorganic oxide, said network having a plurality of metaloxy species bonded thereto, said metal oxy species being selected fromthe group consisting of a metal oxy halide, an alkyl metal oxy halide,and an alkyl metal oxy.
 2. The method of claim 1 wherein theperfluorinated ion-exchange polymer contains sulfonic acid groups andmetal halide sulfonate groups and is about 10 to about 25% by weight ofthe microcomposite.
 3. The method of claim 1 wherein the inorganic oxideof the network is silica and the metal oxy species is aluminum chloride.